Pick box for housing a mineral cutter pick

ABSTRACT

A “wet” pick box  1  comprises a body member  2,  adapted in use to be welded to a rotary cutting head, whilst an aperture  5  is provided in the body member. Bores  15, 16  in the body member define an internal water course  6  connectable, at an inlet end  7 , to a source of pressurised water; an aperture  8  in the body member is adapted to house a water discharge nozzle and is connected to an outlet end  9  of the watercourse  6.  A tapped hole  10  intersects the bores  16  and a member  11 A or  11 B is insertable into, and removable from, the hole  10.  The invention also includes a rotary mineral cutting head to which a plurality of such pick boxes are welded.

FIELD OF THE INVENTION

[0001] This invention relates to a pick box for releasably housing acutter pick, with the box adapted in use, to be mounted on a rotarycutting head of a shearer drum for mineral winning operations, or of arock culling head for underground roadway or tunnel driving operations,or also for mineral winning, or, for surface use, of a road planingmachine as part of highway maintenance.

BACKGROUND OF THE INVENTION

[0002] All boxes, whether produced as steel castings or forgings, havean aperture to receive the shank of a cutter pick, the aperturediminishing the material and hence strength of the box and thusunavoidably creating an area of weakness, and hence breakage in extremecutting conditions eg when encountering a band of hard rock or wheninadvertently striking a metal object such as a roof beam, strata anchoretc.

[0003] Furthermore, when considering round pick shanks and hence roundbox apertures, the setting angle applied to the box on the rotarycutting head to give the correct cutting attitude of the pick, adds tothe vulnerability of the box. The introduction of a sleeve between thepick shanks and the bore aperture reduces further the section of the boxmaterial remaining. In addition, current developments in box designinclude “wet” systems, fed by internal watercourse bores; which boresagain create structural weakness to the box.

[0004] Apart from wear, “wet” boxes are prone, in general to twofailings:

[0005] 1. loss of system pressure when boxes are broken below theirwater carrying bores, and

[0006] 2. internal blockage from water home debris.

[0007] Whilst a rotary cutting head or shearer drum may have 50 or morepick boxes, the breakage of one or two boxes will not greatly impair thecutting efficiency and the practice is to continue the use of a rotarymember with broken boxes until say a scheduled maintenance period isreached, because a broken box requires the broken box(es) to be burntoff, and a replacement box to be welded on, and as such operations arenot allowed by law in UK coal, mines the rotary member must be removedfrom the mining or tunnelling machine and transported either to thesurface or to a safe area, for welding.

[0008] Apart from the above problem, and as indicated previously abroken box exposes a water bore, so that, instead of the water flowbeing throttled by a relatively small diameter spray nozzle or dischargeof a spray at the required area, large quantities of water are wasted byuncontrolled emission from an exposed bore, resulting in diminished, orineffective flow to the remaining spray nozzles, as well as inconvenientdeposit of water in the mining etc area.

OBJECT OF THE PRESENT INVENTION

[0009] A basic object of the present invention is the provision of animproved “wet” pick box.

[0010] Summary of a First Aspect of the Invention

[0011] According to the present invention, there is provided a “wet”pick box for releasably housing a shank of a mineral cutter pick, thebox comprising:

[0012] (i) a body member, adapted in use to be secured to a rotarymember, aid having a front end and a rear end (having regard to thedirections of rotation of the rotary member, in use);

[0013] (ii) an aperture in the body member corresponding cross-sectionto that of the sleeve or of a shank of a cutter pick intended, in use,to be carried by the box;

[0014] (iii) at least one bore in the body member defining an internalwater course connectable, at an inlet end, to a source of pressurisedwater;

[0015] (iv) a water discharge nozzle also housed in an aperture in thebody member and connected to an outlet end of the watercourse;

[0016] (v) a hole intersecting the bore towards tie rear end of the box,and

[0017] (vi) a member insertable into, and removable from the hole and,in one embodiment, to permit water flow, and in another embodimentblanking-off the bore to prevent water flow.

[0018] Advantages of the Invention

[0019] By the provision of the alternative insertable members, onemember, for normal operation with a non-broken box, to permit water flowand may carry a water filter eg a gauze, to prevent debris entrained inthe water supply reaching the spray nozzle and blocking same.

[0020] Importantly, if a box breakage should occur, then the flowpermitting member is removed and replaced by a blanking-off member,which blocks water flow aid hence prevents uncontrolled emission ordischarge of water from a bore exposed by the breakage, thus maintainingthe water pressure for the remainder of the spray nozzles.

[0021] Preferred or Optional Features of the Invention

[0022] The hole intersecting the bore is a tapped hole, with theinsertable member having an external thread.

[0023] The insertable member in one embodiment carries a filter throughwhich the water must flow to reach the spray nozzle.

[0024] The filter is a thimble shaped metal gauze located in a receivingrecess of the insertable member.

[0025] The insertable member, of any form carries at least one scalingring.

[0026] The aperture in the body member is hexagonal.

[0027] A tapped hole is provided at or towards a front end of the box,to receive a water spray nozzle.

[0028] The internal watercourse is defined by at least two linear boresintersecting at a side face of the box at a side chamber which isclosed-off by a cover plate, which is removable to expose ends of theintersecting bores, whereby a rod may be inserted to clear debrisblocking the bore(s).

[0029] Summary of a Second Aspect of the Invention

[0030] According to a second aspect of the invention, there is provideda rotary, mineral cutting head to which a plurality of pick boxes inaccordance with the first aspect, are welded.

[0031] The invention will now be described in greater detail, by way ofexample, with reference to the accompanying drawings, in which:

[0032]FIG. 1 is a side elevation of a pick box in accordance with theinvention;

[0033]FIG. 2 is an end elevation of FIG. 1 in the direction of arrow A;and

[0034]FIGS. 3 and 4 show two alternative plugs to be fitted into thepick box of FIGS. 1 and 2.

[0035] A “wet” pick box 1 comprises a body member 2, adapted in use tobe welded to a rotary cutting head, and having a front end 3 and a rearend 4 (having regard to the directions of rotation of the cutting head,in use). The body member 2 is provided with a hexagonal aperture 5 toreceive a sleeve or of a shank of a cutter pick intended, in use, to becarried by, and releasably retained in, the box 2. Multiple bores 15,16, 20 in the body member define an internal water course 6 connectable,at an inlet end 7, to a source of pressurised water, whilst a waterdischarge/spray nozzle (not shown) is also housed in an aperture 8 inthe body member and connected to an outlet end 9 of the watercourse. Atapped hole 10 intersects the bore 16 towards the rear end 4 of the pickbox 1) and a screw threaded plug member 11A is insertable into, andremovable from the hole 10 to permit water flows or alternatively plug11B capable, of blanking-off the bore 5 to prevent water flow. To guardagainst contaminated water being supplied and contaminants eventuallyblocking the spray nozzle, the plug 11A carries a metal gauze filter 12through which the water must flow to reach the spray nozzle, whilst bothplugs 11A and 11B carry deformable sealing rings 13, 14.

[0036] The two linear bores 15, 16 intersect at a side face 17 of thebox 1 at a side chamber 18 which is closed-off by a cover plate 19,which is removable to expose ends of the intersecting bores, whereby arod may be inserted to clear any debris blocking the bores 15 or 16.

1. A “wet” pick box for releasably housing a shank of a mineral cutterpick, the box comprising: (i) a body member, adapted in use to besecured to a rotary member, and having a front end and a rear end(having regard to the directions of rotation of the rotary member, inuse); (ii) a first aperture in said body member correspondingcross-section to that of a sleeve or of a shank of a cutter pickintended, in use, to be inserted into said aperture; (iii) an internalwater course in said body member defined by at least one bore andconnectable, at an inlet end, to a source of pressurised water; (iv) asecond aperture in said body member adapted to house a water spraynozzle and said second aperture and connected to an outlet end of saidwatercourse; (v) a hole intersecting said bore towards said rear end ofsaid box, and (vi) a member insertable into, and removable from the holeand capable, in one mode, of permitting water flow, and in another modeblanking-off the bore and preventing water flow.
 2. A pick box asclaimed in claim 1, wherein said hole intersecting said bore is a tappedhole, with said insertable member having an external thread.
 3. A pickbox as claimed in claim 1, wherein, in one embodiment, said insertablemember carries a filter through which the water must flow to reach saidspray nozzle.
 4. A pick box as claimed in claim 3, wherein said filteris a thimble shaped metal gauze located in a receiving recess of saidinsertable member.
 5. A pick box as claimed in claim 1, wherein, inanother embodiment said insertable member constitutes a blanking-offplug to prevent water flow.
 6. A pick box as claimed in claim 1, whereinat lest one sealing ring is carried by said insertable member.
 7. A pickbox as claimed in claim 1 wherein said first aperture in said bodymember is hexagonal.
 8. A pick box as claimed in claim 1, wherein saidsecond aperture is a tapped hole.
 9. A pick box as claimed in claim 1,wherein at least two linear bores define said internal watercourse, saidtwo linear bores intersecting at a side face of said box at a sidechamber of said box which side chamber is closed-off by a cover plate,which cover plate is removable to expose ends of said intersectingbores, whereby a rod may be inserted to clear any debris blocking thebore(s).
 10. A rotary, mineral cutting head to which a plurality of pickboxes are welded, each pick box comprising: (i) a body member, adaptedin use to be secured to a rotary member, and having a front end and arear end (having regard to the directions of rotation of the rotarymember in use); (ii) a first aperture in said body member correspondingcross-section to that of a sleeve or of a shank of a clutter pickintended, in use, to be inserted into said aperture; (iii) an internalwater course in said body member defined by at least one bore andconnectable, at an inlet end, to a source of pressurised water; (iv) asecond aperture in said body member adapted to house a water spraynozzle and said second aperture and connected to an outlet end of saidwatercourse; (v) a hole intersecting said bore towards said rear end ofsaid box, and (vi) a member insertable into, and removable from the holeand capable, in one mode, of permitting water flow, and in another modeblanking-off the bore and preventing water flow.